Zheleznogorsk is a closed town in Krasnoyarsk Krai, Russia.It was established in 1950 for the production of weapons-grade plutonium. It was a secret town in the Soviet Union until President Boris Yeltsin decreed in 1992 that such places could use their historical names. Before then, the town had not appeared on any official maps. The town was also known as Soctown, Iron City, the Nine and Atom Town.

Miasto Żeleznogorsk w Kraju Krasnojarskim powstało w 1950 roku jako miejsce produkcji plutonu dla wojska. Do dzisiejszych czasów jest to miasto zamknięte i obecnie pozostaje w gestii agencji Rosatom.